Apoptosis is the process by which cells in the body die in a controlled and predictable way because they have DNA damage or are no longer needed. The term comes from a Greek word meaning “falling off,” as in leaves falling from a tree.
When a cell undergoes apoptosis, it shrinks and pulls away from its neighbors. As the cytoskeleton that gives it shape and structure collapses, the envelope around the cell’s nucleus breaks down, and its DNA breaks into pieces. Its surface changes, signaling its death to other cells and leading a healthy cell to engulf the dying one and recycle its components.
All cells contain the instructions and tools needed for apoptosis, and the process works in harmony with cell division, or mitosis, to keep our tissues and organs healthy. Scientists estimate that in the average adult, about 10 billion cells undergo apoptosis and are replaced every day.
An imbalance between mitosis and apoptosis can cause disease. Unchecked mitosis can lead to cancer, and excessive apoptosis may contribute to neurodegenerative diseases such as Alzheimer’s, Parkinson’s, and Lou Gehrig’s.
NIGMS-Funded Apoptosis ResearchMany scientists supported by NIGMS study apoptosis. Some of these researchers are:
- Developing tools to better observe apoptosis
- Determining how a drug triggers controlled death in bone cancer cells and how to best deliver the drug
- Investigating the role of intestinal cell death to help prevent critical illness associated with gut injuries
- Studying how apoptosis helps ensure the development of only high-quality egg cells, particularly when organisms are stressed by environmental factors, such as high or low temperatures
Learn about other scientific terms with the NIGMS glossary.